Centrifuge



Fel 8, 1966 G. HULTscH ETAL 3,233,735

CENTRIFUGE Filed Jan. 24, 1965 3 Sheets-Shea?l l wim #fram/Er Feb. 8,1966 G. HuLTscH ETAL 3,233,735

CENTRIFUGE Filed Jan. 24, 1963 :s sheets-sheet 2 Feb. 8, 1966 G. HuLTscHETAL 3,233,735

CENTRIFUGE Filed Jan, 24, 1963 3 Sheets-Sheet 3 United States Patent()3,233,735 CENTREFUGE Guenther Hultsch, Munich, and Walter Koecher,Munich- ()bermenzing, Germany, assignors to Krauss-MaeiAktiengesellschaft, Munich-Allach, Germany Filed Jian. 24, 1963, Ser.No. 253,618 23 Claims. (Cl. Zitti- 367) The present invention relates tocentrifuges, and more particularly to a centrifuge of the type whereinthe barrel or drum is rotated about two axes which intersect or crosseach other.

It is an important object of this invention to provide a very simpleadjusting or regulating device which enables an operator to adjust theangle between such intersecting axes when the drum is at a standstill orwhen the centrifuge is in actual use.

Another object of the invention is to provide an improved connection orsystem of joints between the drum and the shafts which form part of themeans for driving the drum about two intersecting axes.

A further object of the instant invention is to provide a centrifuge ofthe type which embodies a conical drum and wherein the drum isconstructed and assembled in such a way that the heavy, e.g., solidfraction may be separated from the light, e.g., liquid fraction in aseries of immediately following consecutive steps and wherein the drumcomprises specially constructed means for facilitating expulsion ofheavy fraction from the collecting compartment into which the heavyfraction is being discharged when the centrifuge is in actual use.

Still another object of the invention is to provide a centrifuge of theabove entitled characteristics wherein the joint between the shafts andthe drum permits adjustments in the inclination of the axis of the drumnot only when the drum is arrested but also when the drum performs acomposite angular movement about its own axis and about the axes of theshafts.

An additional object of the invention is to provide a novel system ofjoints for the drum of a centrifuge of the type which is especiallysuited for separation of liquor from crystalline substances.

A concomitant object of the invention is to provide a system of jointsfor a centrifuge of the above outlined characteristics which enables thedrum to assume an infinite number of different angular positions withrespect to the axes of the driving shafts and which may be readilyinstalled in many types of conventional centrifuges withoutnecessitating substantial changes in the construction of such apparatus.

A further object of our invention is to provide a system of joints forthe drum of a centrifuge wherein the inclination of the axis about whichthe drum is caused to spin may be adjusted by mechanical or by hydraulicmeans.

An additional object of the invention is to provide a centrifuge whichmay be rapidly converted for treatment of different materials withoutnecessitating any dismantling or exchange of its parts and withoutnecessitating any or by requiring only short interruptions in theoperation of the centrifuge.

With the above objects in View, the invention resides in the provisionof a centrifuge which comprises a first shaft, a second shaft which iscoaxial with and which surrounds the first shaft, an upwardly andoutwardly diverging rotary conical drum which is adapted to receive thematerial to be centrifuged and which comprises a fluid-permeable outermantle whose axis is normally inclined with respect to the common axisof the shafts and wherein the separation of light and heavy fractionstakes place so that the light fraction passes through the mantle andthat the heavy fraction travels upwardly and is discharged bycentrifugal force over the upper edge portion of the mantle, a uni- ICCversal joint drivingly connecting the drum with the first shaft so thatthe drum spins about its axis when the first shaft rotates, and anarticulated joint drivingly connecting the second shaft with the drum sothat the axis of the drum travels about the common axis of the shaftsalong a conical surface when the second shaft rotates.

In accordance with our invention7 the inclination of the drum withrespect to the common axis of the shafts is adjustable, either when thecentrifuge is idle or when the centrifuge is in actual use. This may beachieved by mounting the rst shaft in such a way that it is axiallyreciprocable in the second shaft and by providing suitable means whichtransforms axial movements of the first shaft into angular displacementsof the articulated joint to thereby change the inclination of the drum.If the inclination of the drum is to be adjusted when the centrifuge isat a standstill, the construction of the apparatus may be simplified byutilizing means which releasably fixes the component parts of thearticulated joint in a selected position corresponding to a desiredinclination of the drum.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following detailed description of certainspecific embodiments with reference to the accompanying drawings, inwhich:

FIG. 1 is a central vertical section through a centrifuge which embodiesone form of our invention and wherein the drum is driven by two coaxialshafts;

FIG. 2 is an enlarged central vertical section through the system ofjoints which connects the shafts with the drum;

FIG. 3 is a horizontal section as seen in the direction of arrows fromthe line III-III of FIG. 2;

FIG. 4 is a central vertical section through a pair of joints one ofwhich is different from the corresponding joint of FIG. 2;

FIG. 5 is a central vertical section through a pair of joints one ofwhich may be fixed manually in any of a series of different positions ofadjustment; and

FIG. 6 is a fragmentary central vertical section through a modifiedcentrifuge which comprises a different housing and a differentlyconstructed drum.

Referring now in greater detail to the illustrated embodiments, andfirst to FIG. l, there is shown a centrifuge A which comprises acomposite housing it) mounted on spaced ground-contacting legs 10a andaccommodating a specially constructed and specially mounted rotary drumor basket 1. This drum comprises an upwardly and outwardly diverginghollow conical huid-permeable outer mantle 2 and a hollow conical innermantle 4 which is surrounded by the outer mantle 2, which divergesupwardly and inwardly, and whose central portion or hub 4a is detachablyfastened to a system K of joints one of which is a universal joint ofthe type known as Cardan joint. Material to be centrifuged is fedcontinuously through a centrally located hopper 6 mounted in the topwall 10b of the housing 10 and discharging such material onto the hub 4awhence the material descends along the inner side of an outwardly anddownwardly diverging hollow conical shield or guide 7 which is securedto the inner mantle 4 by stay bolts 4b and which insures that newlyadmitted material cannot mix with the fractions revolving in theseparating or centrifuging chamber 5 of the drum 1. In other words, theshield 7 compels newly admitted material to descend along the outer sideof the inner mantle 4 and to enter the lowermost zone of the chamber Sbetween the meeting lower edge portions of the mantles 2, 4.

The housing denes a first annular collecting compartment 9 whichsurrounds the major part of the outer mantle 2 and which receives thelight fraction of material which is being centrifuged in the chamber 5,such light fraction passing throu-gh the perforations or pores of theouter mantle 2 and impinging against a downwardly and outwardlydiverging conical skirt 8 which is secured to the larger-diameter upperedge portion 3 of and which surrounds the mantle 2 so as to deflect thelight fraction into the compartment 9. The housing 10 further defines asecond or upper annular compartment 11 which collects the heavy fractionof centrifuged material and which is sealed from the lower chamber 9save for a gap 11a defined by the skirt 8 and by an upwardly andinwardly coverging wall portion 10c of the housing 10, such gas 11abeing necessary to prevent frictional engagement between the skirt andthe housing. The heavy fraction travels upwardly along the inner side ofthe outer mantle 2 and toward and beyond the upper edge portion 3 ofthis mantle to be ejected by centrifugal force so that it automaticallyaccumulates in the chamber 11 whence it may be removed at certainintervals or whence it may be evacuated automatically, for example, fromthe bottom zone of the chamber 11, by means of a screw conveyor or thelike, not shown. The centrifuge A of FIGS. 1 to 3 is especially suitedfor separating liquor from crystalline substances and for avoiding roughtreatment of such substances during transfer into the compartment 11,but it is self-evident that the centrifuge may be put to many other useswithout in any way departing from the spirit of our invention.

The drum 1 receives motion from two coaxial vertical drive shafts 12,12a the latter of which assumes the form of a hollow tube and surroundsthe inner shaft 12. The shafts 12, 12a are driven by a variable-speedelectric motor 16 which is secured to the housing 10 by a bracket 16aand whose vertical output shaft 1Gb carries at its opposite ends a pairof sheaves 17, 17a. The lower end portion of the inner shaft 12 projectsdownwardly and beyond the lower end portion of the outer shaft 12a andcarries a sheave 14 driven by an endless V-belt a which is trainedaround the sheave 17a. A similar endless V-belt 15 is trained around thesheave 17 and drives a fourth sheave 13 which is non-rotatably securedto the lower end portion of the outer shaft 12a. The parts 17a, 15a, 14and 17, 15, -13 constitute two belt transmissions which respectivelytransmit motion to the drive shafts 12, 12a. The outer shaft 12a rotatesin two radial antifriction bearings 18 which are accommodated in anopening 19b provided in they sleeve-like median portion 19a of a bottomwall 19 forming part of the housing 10. An annular plate 19C closes thelower end of the opening 19h, and a similar annular plate 19d isprovided to close the upper end of this opening. It will be noted thatthe inner race of t-he upper radial bearing 13 abuts against an externalshoulder of the outer shaft 12a so that the latter is held against axialdisplacement in downward direction. The diameters of the sheaves 13, 14are different and it is assumed that the r.p.m. of the inner shaft 12exceeds the r.p.m. of the outer shaft 12a.

The lower portion of the inner shaft 12 rotates in a thrust bearing 20which is accommodated in a bearing sleeve 21 having an externallythreaded upper end portion 22 which mates with an internally threadedhousing portion here shown as a retaining ring or nut 23 which issecured to the bottom wall 19 by a series of radial arms or spokes 24.The bearing sleeve 21 carries a sprocket wheel 25 which may be driven bya suitable motor (not shown) through a chain or the like and whichserves as a means for axially adjusting the inner shaft 12 with respectto the outer shaft 12a and for thereby adjusting the inclination of theaxis of the drum 1 with respect to the common axis of the shafts 12,12a.

Referring to FIGS. 2 and 3, the upper end portion of the outer shaft 12ais rigid or integral with a hollow cylindrical socket or shell 26 whoseaxis X is horizontal and which accommodates a roller 27, the latterbeing free to turn about the axis X. The roller 27 is formed with a flatupper side 28 and with a at underside 28a, the latter being parallelwith the upper side 28 and being provided with an upwardly extendingcylindrical bore having a larger-diameter lower section 31 and asmallerdiameter upper section 31a which terminates in the upper side 2S.The axis Z of the bore 31, 31a coincides with the axis of the drum 1 andis perpendicular to the common axis X of the parts 26, 27. rI`he axiallength of the upper section 31a preferably approximates the axial lengthof the lower section 31. The socket 26 and the roller 27 togetherconstitute an articulated joint 29 which permits tilting movements ofthe drum 1 in a vertical plane, i.e., about the axis X. When the joint29 permits the drum 1 to assume a position in which the common axis Z ofthe mantles 2, 4 is inclined with respect to the common axis Y of thedrive shafts 12, 12a, the drum revolves about the axis Y andsimultaneously spins about the axis Z without any wobbling. To reducethe effect of unbalance of the drum 1, the center 1a of gravity of thisdrum is preferably located in the common axis X of the parts 26, 27, andmore particularly in the point of intersection between the axis X andthe common axis Y of the shafts 12, 12a. In other words, the axes X, Y,Z intersect each other in the center 1a. The ends of the socket 26 areclosed by two detachable vertical end plates 30, see FIG. 3, which holdthe roller 27 against axial displacements in the concave internal spaceof the socket. In other words, the walls 30 serve to hold the rolleragainst movements other than about the horizontal axis X. The internalsurface bounding the lower section 31 of the through bore in the roller27 is formed with threads 33 which mate with external threads of aretaining ring 42, the latter serving as a means for retaining thecylindrical wall portion 40 of an inverted cup shaped member 41 which isaccommodated in the upper bore section 31a. The wall portion 4u isformed with a diametral bore 40a for a rotary horizontal coupling pin39, and the lower portion of this wall portion forms a collar 40h whichrests on the ring 42 and which is normally spaced from an internalshoulder 32 of the roller 27, this shoulder dividing the bore sections31, 31a from each other. The top wall 43 of the cupped member 41 carriesan upwardly extending stub shaft 44 of polygonal outline which isreceived in a complementary aperture of the hub 4a so that the drum 1 iscompelled to share angular movements of the cupped member.

The upper end portion 12A of the inner shaft 12 is formed with ashoulder 34 for a rotatable annulus 35, and this end portion 12A isprovided with external threads which mate with the threads of a nut 36serving as a means to hold the annulus 35 against axial movements withrespect to the inner shaft. A stub shaft 37 which constitutes the upperterminal of the end portion 12A is formed with a diametral slot 38, seeFIG. 3, for the central portion of the .pin 39.

The cupped member 41 and the pin 39 together constitute one component orfork of a universal joint. The other component or fork of this universaljoint is formed by the slotted stubbed shaft 37 of the inner shaft 12.

The inclination of the axis Z of the drum 1 with respect to the verticalaxis Y of the shafts 12, 12a may be adjusted by radial bolts or studs 45which project from the periphery of the annulus 35 and which areaccommodated in inclined recesses or grooves 46 of the roller 27. Thecommon axis of the bolts 45 is parallel with the axis X. If the shaft 12is axially displaced with respect to the shaft 12a, i.e., in response torotation of the bearing sleeve 21 by the sprocket 25, the bolts 45 slidein the respective recesses 46 and change the inclination of the drum 1.If

the shaft 12 is lifted, the bolts 45 cause the'drum 1 to turn in ananticlockwise direction, as viewed in FIG. 2, because the recesses areinclined upwardly and to the left so that the angle a between the axes Yand Z becomes smaller. The roller 27 shares such angular displacement ofthe drum and turns about the horizontal axis X to thereby change theinclination of the upper fork 41.

An import-ant advantage of such construction of the universal joint isthat the inclination of the axis Z of the drum 1 may be changed when thecentrifuge is in actual use, namely, when the motor 16 drives the shafts12, 12a.

The articulated joint 29 may be modified in a number of ways withoutdeparting from the spirit of my invention. For example, the parts 26, 27may be replaced by a true ball and socket joint wherein the roller 27 isof spherical shape and is 4formed with a pair of arcuate ribs arrangedin opposed meridian planes and fitting into complementary channels ofthe socket to insure that the roller shares all angular movements of thesocket. Such ribs and channels permit tilting of the roller in a singleplane about an axis corresponding to the axis X of FIG. 3. It is alsopossible to provide the spherical roller of a true ball and socket jointwith four equidistant projections which are disposed in a commonequatorial plane and to form the socket with two circular channelsdisposed in two meridian planes and each of which receives twoprojections so that the roller is tiltable in each of the two meridianplanes. Such modifications are so obvious that they can be readilycomprehended without additional illustrations. Ail that is necessary toprovide on the roller 27 and on the socket 26 some means which (as thebolts 45 and recesses 4o) is capable of transforming axial movements ofthe inner shaft 12 into angular movements of the fork 41 and hence ofthe drum 1.

The centrifuge of FIGS. 1 to 3 operates in the following manner:

When the motor 16 is started, the transmission including the sheave 14drives the inner shaft 12 which in turn causes the drum 1 to spin aboutthe axis Z. Such spinning movement is transmitted to the drum by theuniversal joint whose lower fork 37 is rigid with the upper end portionof the shaft 12 and whose upper fork 41 is rigid with the centralportion of hub 4a.

At the same time, the belt transmission including the sheave 13 drivesthe outer shaft 12a. which rotates the articulated joint 29 whereby theroller 27 compels the drum 1 to revolve about the axis Y so that theaxis Z describes a conical surface whose conicity corresponds to theangle a.

lf the operator desires to change the angle a, he drives the sprocket 25in a direction to lift or to lower the inner shaft 12 whereby the bolts4S travel in the respective recesses d6 and cause the roiler 27 to betilted about the horizontal axis X. The roller 27 changes theinclination of the upper fork 41 and of the shaft 44 which in turnchanges the angular position of the axis Z. Such adjustments may be madewhen the motor 16 is running.

A very important advantage of the centrifuge A is that the angle a maybe adjusted as often as desired, that this angle may be adjusted whenthe centrifuge is in actual use, and that this angie may be changed toan infinite numberof magnitudes so that the centrifuge may be used inconnection with a wide variety of materials. Thus, by changing theinclination of the axis Z, one may select the angle a in a way as .toinsure that a heavy fraction of given specific weight, of given moisturecontent and of given consistency will be discharged from the chamber 5at a predetermined rate. By `reducing the inclination of the axis Z, onecan insure that the heavy fraction remains in the chamber 5 for a longerperiod of time and that it loses a greater percentage of light fractionprior to being evacuated into the upper compartment 11. In addition, bychanging the inclinaiton of the axis Z, the operator may change theangle of repose (slope) of material in the chamber 5. The heavy fractionis being discharged over that zone of the edge portion 3 which ismomentarily located at the lowest level, i.e., which is nearest to theupper edge of the skirt 8. of the upper edge portion 3 with respect to ahorizontal plane determines the rate at which the heavy fraction isbeing discharged into the compartment 11, and this inclination equalsthe angle between the axes Y and Z. Thus, by providing the centrifugewith a device which can change the angle oc, We may utilize thecentrifuge of our invention in connection with different materialswithout necessitating any interruptions in the operation of theapparatus and without necessitating dismantling of any parts. In certainconventional centrifuges of which we have knowledge at this time, thejoints' between the driving shafts and the central portion of the drummust be taken apart or exchanged if it is desired to change theinclination of the drum. Therefore, such conventional oentrifuges mustbe furnished with two or more sets of joints in order to insure that thedrum may be used for seperation of different materials. Whenever suchconventional centrifuges are converted for separation of differentmaterials, it is necessary to arrest the motor, to remove the drum, andto exchange the joints in order to change the inclination of the drumaxis with respect to the axes of the shafts.

For example, when the characteristics of the material which is beingadmitted through the hopper 6 are known, the angle or may be adjusted inadvance and thereupon remains unchanged during the entire centrifugingoperation. On the other hand, if the characteristics of the materialwhich is to becentrifuged are unknown, the operator experiments byadjusting the axial position of the inner shaft 12 until the heavyfraction begins to enter the upper compartment 11 at a desired rate perunit of time and contains a desired perecentage of light fraction or isfree of any traces of light fraction. The speed at which the fractionsare separated may be varied by changing the r.p.m. of the shaft 12and/or 12a in response to adjustments in the r.p.m. of the output shaft1617.

Another important advantage of the centrifuge A is that the inclinationof the axis Z `may be adjusted from a readily `accessible point of thehousing, i.e., beneath the raised bottom `wall 19. It is immaterialwhether the inclination is adjusted manually (e.g., by means of a toolwhich engages the bearing sleeve 21) or by means of a motor land througha transmission (such as the chain transmission of which the sprocket 2Sconstitutes .a component part). If the sleeve 21 is rotated manually,its periphery may Ibe of hexagonal or other non-circular con- -tour sothat it may be engaged by a conventional wrench or the like.

The composite movement of the drum 1 may be cornpared with the movementof a top which spins about its own yaxis and Awhose axis simultaneouslyrevolves `about a vertical axis to describe a hollow conical surface. Inother words, the drum need not wobble in a manner as is known from theart of swash plates for pumps and simiiar hydrodynamic machines.Consequently, the wear on the bearings is minimal .and such bearingsremain usable for very long periods of time.

Referring to FIG. 4, there is shown a portion of a different centrifugewherein the inclination of the stub shaft 144 (and hence of the axis Z)may be ladjusted by `a hydraulic device. The cupped member 141, the ring142, the horizontal coupling pin 139 and the stub shaft 137 allcooperate in the same manner as members 41, d2, '39 and 37,respectively, previously described with `reference to `FGS. 2 and 3. Thehollow socket 12d is asymmetric with respect to the hollow outer shaft112e and the space 147 between the roller 127 and the lower portion ofthe socket 126 is lled with a non-compressible fluid, this fluid alsofilling the internal space 112B of the shaft 112g. When the inner shaft112 is moved upwardly, it expels some fluid from the internal space 112Bwhereby the fluid The inclination of the plane compels the roller 127 topivot about the horizontal axis of the joint `129, such pivotal movementtaking place in an anticlockwise direction, as viewed in FIG. 4. Whenthe sli-aft 112 moves downwardly, the fluid entrapped in the space 147causes the roller 1:27 and the drum to pivot in a clockwise direction. l

In other words, vthe specially configurated (assymetric) roller 127 andthe fiuid filling the space 147 perform the function of the bolts l45and recesses 46 in that they transform axial movements of the innershaft into angular displacements of the stub shaft 144 about thehorizontal axis of the soc-ket 125.

The connection between a drum and the driver shafts may be simplied ifthe centrifuge is constructed in such :a way that the inclination of thedrum is adjustable only when the apparatus is at a standstill. In suchinstances (see FIG. the inner shaft 212 need not be mounted for axialmovement so that the bearing sleeve (corresponding to the sleeve 21 ofFIG. l) may be permanently fixed to the housing. In addition, the ring35, the bolts 45 and the recesses to may be dispensed with. The socket226 is formed with two tapped bores 24S for holding means here shown asscrew bolts 249 which engage and normally hold the roller 227 againstangular displacements with resp-ect tothe socket 226. When the shafts212, 212a are at a standstill, the operator loosens the screw bolts 249and adjusts the inclination of the r-oller 227 whereupon the bolts 249fare tightened again to retain the roller in the newly selected positionof adjustment with respect to the socket 226. The construction of theuniversal joint may be the same as in FIGS. 2 and 3. In thisernbodiment, the screw 'bolts 249 which are fixed to the socket 226serve as a means for maintaining the drum in a selected angular positionwith respect to the socket. The cupped member 241, the ring 242, thehorizontal coupling pin 239 and the stub shaft 237 all cooperate in thesame manner as previously described with reference to FIGS. 2 and 3,relative lto members 41, 42, 39 and 3'7, respectiv-ely.

FIG. 6 illustrates a portion of la centrifuge A wherein the uppercompartment 311 is bounded by a hollow spherical wall portion 356forming part of a modified housing 310. The curvature of this wallportion 35@ has its center in the point `of intersection between thecommon vertical axis Y of the drive -shafts 12, 12a and the horizontalaxis of the roller-andeocket joint which is not shown in FIG. 6 becauseit is assumed to be identical with the joint 29 of FIGS. 2 and 3. Thedrum 3&1 comprises an outer mantle 362 which include-s a hollow conicalupper section 355 and a hollow conical lower section 354. The upper edgeportion 353 of the upper section 355 includes a horizontal collar 353gwhich is provided with outwardly extending vanes or blades 352 servingas a means for expelling the heavy fraction into a tangential outlet 351which communicates with the compartment 311. The angle of divergence ofthe upper section 355 exceeds the angle of divergence of the lowersection 354. Thus, the tendency of the heavy fraction to move upwardlyand toward the edge portion or lip 353 is less pronounced while theheavy fraction is still contained in the lower zone of the centrifugingchamber 365, i.e., in that zone which is immediately adjacent to thebottom 364 and which is Surrounded by the lower section 354 wherein themajor part of the separating action takes place. In other words, at thetime the heavy fraction reaches the upper section 355, the major part ofthe light fraction has -already passed through the perforations of thelower section 354!f to accumulate in the lower compartment 309.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featuresthat, from the standpoint of [prio art, fairly constitute essentialcharacteristics of the generic and specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of the shaftshaving an upper end portion; means for driving said shafts; a rotarycentrifuging drum having an axis normally inclined with respect to andintersecting the common axis of said shafts, said drum comprising lacentral portion located above the upper end portions; a universal jointcomprising a first component rigid with the end portion of said firstshaft and a second component driven by said first component and rigidwith said central portion so that the drum spins about its axis inresponse to rotation of said first shaft; an angularly adjustablearticulated joint comprising a socket rigid with the end portion of saidsecond shaft` and a roller received 4in and sharing rotary movements ofsaid socket in response to rotation of saidsecond shaft, said rollerrotatably receiving said second component and being turnable in saidsocket about a horizontal axis which intersects the axis of the drum inthe point wherein the axis of the drum intersects said common axiswhereby, in response to turning of said roller, the second componentchanges the inclination of the axis of the drum with respect to saidcommon axis; adjusting means for turning the roller about saidhorizontal axis to any one of a plurality of predetermined positions;and means for maintaining the axis of said drum in such predeterminedposition.

2. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of the ,shaftshaving an upper end portion; means for driving said shafts; bearingmeans axially reciprocably supporting said first shaft in said secondshaft; a rotary centrifuging drum having an axis normally inclined withrespect to and intersecting the common axis of said shafts, said drumcomprising a central portion located above the upper end portions; auniversal joint comprising a first component rigid with the end portionof said first shaft and a second component driven by said firstcomponent and rigid with said central portion so that the drum spinsabout its axis in response to rotation of said first shaft; an angularlyadjustable articulated joint comprising a socket rigid with the endportion of said second shaft and a roller received in and sharing rotaymovements of said socket in response to rotation of said second shaft,said roller rotatably receiving said second component and being turnablein said socket about a horizontal axis which intersects the axis of thedrum in the point wherein the axis of the drum intersects said commonaxis whereby, in response to turning of said roller, the secondcomponent changes the inclination of the axis of the drum with respectto said common axis; and adjusting means for turning the roller aboutsaid horizontal axis, said adjustingmeans comprising means for axiallymoving said first shaft with respect to vsaid second shaft, and meansfor transforming axial movements of said first shaft into angularmovements of said roller about said horizontal axis.

3. A combination as set forth in claim 2, wherein the means for axiallymoving said first shaft comprises a motor-driven member drivinglyconnected with said bearing means and wherein said bearing means isaxially movable with said first shaft in response to rotation thereof.

4. A combination as set forth in claim 3, further comprising a housingfor said drum, said housing having a threaded portion mating withthreads provided on said bearing means.

5. In a centrifuge, in combination, va first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of the shafts.having an upper end portion; a rotary centrifuging drum having an axiswhich is normally inclined with respect to the common axis of saidshafts,

and comprising a central portion located above the upper end portionsand a fluid-permeable conical outer mantle which diverges upwardly andoutwardly; a universal joint drivingly connecting said central portionwith kthe upper end portion of said rst shaft whereby the drum spinsabout its axis in response to rotation of said first shaft; an angularlyadjustable articulated joint drivingly connecting said central portionwith the upper end portion of said second shaft so that the axis of saiddrum travels about the common axis of said shafts in response torotation of said second shaft; and adjusting means for adjusting theinclination of the axis of saidy drum with respect to said common axis,said adjusting means comprising means for axially moving one of saidshafts with respect to the other, and means for transforming axialmovements of said one shaft. into angular movements changing theinclination of said axis of said drum with respect to said common axis.

6. A combination as set forth in claim 5, wherein said outer mantlecomprises an upper section and a lower section and wherein the angle ofdivergence of said upper section exceeds the angle of divergen-ce ofsaid lower section.

7. In a centrifuge, in combination, a first shaft; a second shaftcoaxial with and surrounding said first shaft; means for driving theshafts; a centrifuging drum having an axis of rotation which is normallyinclined with respect to the common axis of said shafts; a firstangularly adjustable articulated joint drivingly connecting said firstshaft with said drum so that the drum spins about its axis in responseto rotation of said first shaft; a second angularly adjustablearticulated joint drivingly connecting said drum with said second shaftso that the axis of said drum travels about said common axis in responseto rotation of said second shaft; and adjusting means for adjusting theinclination of the axis of said drum with respect to said common axisduring rotation of said shafts, said adjusting means comprising meansfor axially moving said first ,shaft with respect to said second shaft,and means for transforming axial movements of said first shaft intoangular movements changing the inclination of said axis of said drumwith respect to said common axis.

8. In a centrifuge, in combination, a first shaft; a second shaftcoaxial with and surrounding said first shaft; means for driving theshafts; a centrifuging drum having an axis of rotation which is normallyinclined with respect to the common axis of said shafts; a first angularly adjustable articulated joint drivingly connecting one of saidshafts with said dru-mso that the drum spins about its axis in responseto rotation of said first shaft; a secondangularly adjustablear-ticudated joint drivingly connecting said drum with the other of saidshafts so that the axis of said drum travels about said common axis inresponse -to rotation of said other shaft, said second joint constructedand arranged so as to lbe adjustable to change the inclination of the4axis of said drum to any one of a plurality'of predetermined positions;and means for maintaining the axis of said drum in such predeterminedposition.

9. A combination as set forth in claim 8, wherein said first joint is auniversal join-t .comprising a first component rigid with said firstshaft and a second component driven by said first component and rigidwith said drum, said second joint'coniprising a socket rigid with saidsecond sha-ft and a roller -received 'in said socket and rotatablyreceiving said second component, said roller being turnable in saidsocket about an axis which is perpendicular to saidcornmon axis tothereby change the inclination of said second component and of saiddrum.

10. A combination as set forth in claim 9, further comprising holdingmean-s secured to said socket and adapted to engage sa-id rolller formaintaining the roller in a selected angular position with respect tosaid socket.

11. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of the shaftshaving an upper end portion; means for driving said shafts; a rotarycentrifuging drum having an axis normally inclined with respect -to andintersecting the common axis of said shafts, said drum comprising acentral portion located above the upper end portions; a universal jointcomprising a first component rigid with the end portion of said firstshaft and a second component driven by said first component and rigidwith said central portion so that the drum spins about its axis inresponse to rotation of said first shaft; an angularly adjustablearticulated joint comprising a socket rigid with the end portion of saidsecond shaft and a roller received in and sharing rotary movements ofsaid socket in response to rotation of said second shaft, said rolllerrotatably receiving said second cornponent and being turnable in saidsocket about a single horizontal axis which intersects the axis of thedrum in the point wherein the axis of the drum intersects said commonaxis whereby, -in response to turning of said roller, the secondcomponent changes the inclination of the axis of the drum with respectto said common axis to any one of a ,plurality of predeterminedpositions, said socket comprising means for holding the roller againstmovements other than about said horizontal axis; and adjusting means forturning the roller about said horizontal axis to move said axis of saiddrum to one of said predetermined positions and for maintaining theroller in such adjusted position.

l2.. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of said shaftshaving an upper end portion; means for driving said shafts; a rotarycentrifu-ging drum having an axis normally inclined with respect to andintersecting the common axis of said shafts, Said drum comprising acentral portion located above the upper end portions; a Cardan jointcomprising a first fork rigid with the end portion of said first shaftand a second fork driven by said first fork and rigid with said centralportion so that the drum spins about its axis in response to rotation ofsaid first shaft; an angularly adjustable articulated joint comprising asocket rigid with the end portion of said second shaft and a rollerreceived in and sharing rotary movements of said socket in response torotation of said second shaft, said roller rotatably receiving saidsecond fork and being turnable in said socket about a horizontal axiswhich intersects the axis of the drum in the point wherein the axis ofthe drum intersects said common axis whereby, in response to turning ofsaid roller, the second fork changes the in- -clination of the axis ofthe drum with respect to said common axis to any one of a plurality ofpredetermined positions; and adjusting means for turning the rollerabout said horizontal axis t-o move said axis of said drum to one ofsaid predetermined positions and for maintaining the roller in suchadjusted position.

13. 'A combination as set forth in claim y12, wherein said roller isprovided with a cylindrical bore for said second fork and wherein saidsecond fork comprises a cylindrical wall portion which is rotatable insaid bore.

14. in a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of the shaftshaving-an upper end portion; means for driving said shafts; bearingmeans axially reciprocable supporting said first shaft in said secondshaft; a rotary centrifuging drum having an axis normally inclined -withrespect to and intersecting the common axis of said shafts, said drumcomprising a central portion located above the upper end portions; auniversal joint comprising a first component rigid with the end portionof said first shaft and a second component driven by said firstcomponen-t and rigid with said central portion so that the drum spinsabout its axis in response to rotation of said first shaft; an angularlyadjustable articulated joint comprising a socket rigid with the endportion of said second shaft and a roller received in and sharing rotarymovements of said sockets in response to rotation of said second shaft,said roller rotatably receiving said second component and being turnablein said socket about a horizontal axis which intersects the axis of thedrum in the point wherein the axis of the drum intersects said commonaxis whereby, in response to turning of said roller, the secondcomponent 'changes the inclination of the axis of the dru-m with respectto said common axis -to any one of a plurality of predeterminedpositions; and adjusting means for turning the roller about saidhorizontal axis, said adjusting means comprising means for axiallymoving said first shaft with respect to said second shaft, an annularmember rotatably supported by the upper end portion of said first shaft,and a pair of diametrically arranged bolts exten-ding rad-iallyoutwardly zfrom said annular member and received in inclined recessesprovided in said roller so that axial movements of said first shaftcompel the roller to pivot about said horizontal axis -to move said axisof -said drum to one of said predetermined positions.

15. A combination as set forth in claim 14, wherein said bolts have acommon axis which is parallel with said horizontal axis.

16. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial rwith and surrounding said iirst shaft, each of the shaftshaving an upper end portion and said first shaft being movable axiallywith respect to said second shaft; means Vfor driving said shafts; arotary centrifuging drum having an axis normally inclined with respectto and intersecting the common axis of said shafts, said drum comprisinga central portion located above the upper end portions; a universaljoint comprising a first component rigid with the end portion of saidfirst shaft and a second component driven by said first component andrigid with said central portion so that the dru'rn spins about its axisin response to rotation of said first shaft; an articulated jointcomprising a socket rigid with the end portion of said second shaft, aroller received in and sharing rotary movements of said socket inresponse to rotation of said second shaft,l

said roller rotatably receiving said second component and being turnablein said socket about a horizontal axis which intersects the axis of thedrum in the point` wherein the axis of the drum intersects said commonaxis whereby, in response to turning of said roller, Vthe secondcomponent changes the inclination of the axis of the drum with respectto said com-mon axis, said roller having an underside and beingasymmetric with ,respect to said common axis, and a supply of fluid in.

said socket beneath the underside of said roller; and adjusting meansfor turning the roller about said horizontal axis, said adjusting meanscomprising means for axially displacing said first shaft in said secondshaft whereby the upper end portion of said first shaft compels thefluid to change the angular position of said roller and tethereby changethe inclination of the axis of said drum.

17. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each of the shaftshaving an Iupper end portion and said first shaft being -axially movablein said second shaft; a rotary centrifuging drum having an axis which isnormally inclined with respect -to the common axis of said shafts andcomprising a central portion located above the upper end portions; launiversal joint drivingly connecting said central portion with the upperend portion of said first shaft wherebypthe drum spins about its axis inresponse to rotation of said first shaft; an angularly adjustablearticulated joint dr-ivingly connecting said central portion with theupper end portion of said second shaft so that the axis of said drumtravels about 4the common axis of said shafts in response ,to rotationof said second shaft; and hydraulic means for adjusting the inclinationof the axis of said drum with respect to said common axis in response toaxial movements of said first shaft.

18. In a centrifuge, in combination, a first vertical shaft; a secondshaft coaxial with and surrounding said first shaft, each 'of the shaftshaving an upper end portion; a rotary centrifugin-g drum having an axiswhichis normally inclined with respect to the common axis of saidshafts, said drum comprising a central .portion located above the upperend portions and a iluidperrneable conical outer mantle which divergesupwardly and comprises an upper edge portion; a universal jointdrivingly connect-ing said central portion with the upper end portion ofsaid first shaft whereby the drum spins about its axis in response torotation of said first` shaft; an angularly adjustable articulated jointdrivingly connecting said central portion with the upper end portion ofsaid second shaft so that the axis of said drum travels about thecorn-mon axis of said shafts in response to rotation of said secondshaft; means for adjusting said articulated joint so as to adjust theinclination of the axis of said drum with respect to said common axis toany one of a plurality of predetermined positions; and means formaintaining the Iaxis of said drum in such predetermined position; and ahousing having a fixed wall portion surrounding said upper edge portionin each position of inclination of said drum.

Y 19. A combination as set forth in claim 18, wherein said Wall portionis of hollow spherical shape.

20. A combination as set forth in claim 18, whe-rein said wall port-iondefines a collec-ting compartment for the heavy fraction of materialwhich is being centrifuged in said drum, and further comprising anoutlet extending substantially tangentially of said wall portion andcommunicating with said compartment.

21. A combination as set forth in claim 8, wherein said axis of rotationof said drum intercepts the common axis of said shafts, said drum havinga center of gravity which is located in the point of intersection of theaxes.

22. A combination as set 4forth in claim 8, wherein said means fordriving said first and second shaf-ts are arranged to drive said shaftsat different speeds.

23. A combination as set forth in claim 22, wherein the means fordriving said shaft com-prises a motor having an output shaft, a first'belt transmission driven by said output shaf-t and drivingly connectedwith said first shaft, and a second belt transmission driven by saidoutput shaft and drivingly connected with said second shaft.

References Cited by the Examiner UNITED STATES PATENTS 211,971 2/1897Chrystal et al. 287-12 X 1,603,757 10/1926 Farrell 210--367 1,727,3549/1929 Newhall k 210-78 X 2,806,603 9/1957 Van der Molen 210-380v2,886,179 5/1959 Heckman 210-370 FOREIGN PATENTS 421,336 5/1947 Italy.

OTHER REFERENCES German printed application, 1,072,199, 12/ 1959. Germanprinted application, 1,140,147, 11/ 1962.

REUBEN FRIEDMAN, Primary Examiner.

1. IN A CENTRIFUGE, IN COMBINATION, A FIRST VERTICAL SHAFT; A SECONDSHAFT COAXIAL WITH AND SURROUNDING SAID FIRST SHAFT, EACH OF THE SHAFTSHAVING AN UPPER END PORTION; MEANS FOR DRIVING SAID SHAFTS; A ROTARYCENTRIFUGING DRUM HAVING AN AXIS NORMALLY INCLINED WITH RESPECT TO ANDINTERSECTING THE COMMON AXIS OF SAID SHAFTS, SAID DRUM COMPRISING ACENTRAL PORTION LOCATED ABOVE THE UPPER END PORTIONS; A UNIVERSAL JOINTCOMPRISING A FIRST COMPONENT RIGID WITH THE END PORTION OF SAID FIRSTSHAFT AND A SECOND COMPONENT DRIVEN BY SAID FIRST COMPONENT AND RIGIDWITH SAID CENTRAL PORTION SO THAT THE DRUM SPINS ABOUT ITS AXIS INRESPONSE TO ROTATION OF SAID FIRST SHAFT; AN ANGULARLY ADJUSTABLEARTICULATED JOINT COMPRISING A SOCKET RIGID WITH THE END PORTION OF SAIDSECOND SHAFT AND A ROLLER RECEIVED IN THE SHARING ROTARY MOVEMENTS OFSAID SOCKET IN RESPONSE TO ROTATION OF SAID SECOND SHAFT, SAID ROLLERROTATABLY RECEIVING SAID SECOND COMPONENT AND BEING TURNABLE IN SAIDSOCKET ABOUT A HORIZONTAL AXIS WHICH INTERSECTS THE AXIS OF THE DRUM INTHE POINT WHEREIN THE AXIS OF THE DRUM INTERSECTS SAID COMMON AXISWHEREBY, IN RESPONSE TO TURNING OF SAID ROLLER, THE SECOND COMPONENTCHANGES THE INCLINATION OF THE AXIS OF THE DRUM WITH RESPECT TO SAIDCOMMON AXIS; ADJUSTING MEANS FOR TURNING THE ROLLER ABOUT SAIDHORIZONTAL AXIS TO ANY ONE OF A PLURALITY OF PREDETERMINED POSITIONS;AND MEANS FOR MAINTAINING THE AXIS OF SAID DRUM IN SUCH PREDETERMINEDPOSITION.